In a poor neighborhood in Mexico City, two gangs of kids fight for control of the center where they work as "boleros", musicians or announcers. "Completo" joins the gang led by "Rorro", a rival of the group headed by "Curricán".

Santa is a beautiful and very humble young girl living in Chimalistac, a small and quiet spot south of the 1930's Mexico City. After Santa is cheated by arrogant soldier Marcelino, she's rejected by her family and friends and expelled of Chimalistac. Santa finds shelter in a whorehouse and becomes a cinic and bitter woman, mistreated by bullfighter "Jarameno" and silently loved by blind pianist Hipólito.